Effect of supplementation of ewes in the final third of gestation on the development of their lambs

Abstract

This study examined the effect of different supplementation strategies for ewes in the last third of gestation, kept on a deferred Brachiaria brizantha cv. Marandu pasture, on their performance and the growth curve of their lambs. A total of 54 ewes, of no defined breed, with an average weight of 41.10±3.10 kg, were used in a completely randomized design, divided into three groups (18 ewes per treatment). In total, 61 lambs were born, 28 females and 33 males, with 3.70±0.55 and 3.68±0.69 kg birth weight, respectively. Treatments were as follows: multiple mixture ad libitum, concentrate supplement at 0.4% live weight (LW), and concentrate supplement at 0.8% LW. Average daily weight gain (ADG, g/animal/day) and total weight gain (TWG, kg/animal) were evaluated in ewes and lambs. Reproductive efficiency indices were measured in the ewes and biometric variables in the lambs. The ADG and TWG of ewes in the last third of gestation were higher in animals supplemented at 0.8% LW. Reproductive efficiency results were superior in ewes supplemented at 0.4% LW. The effect of ewe supplementation on lamb growth curve as estimated by the Gompertz model did not reveal differences between the curves of lambs born to ewes that received supplementation at 0.4 and 0.8% LW. However, supplementing ewes with a multiple mixture induced a reduction in the growth curve parameters of their lambs. The use of concentrated supplementation, at levels of 0.4 and 0.8% of LW, provides greater productive and reproductive performance for ewes and lambs.

Productive and Reproductive Efficiency of Ewes Kept on Tropical Pastures as a Function of the Suckling Lamb Treatments

“…To intensify the production of lambs in pastures, supplementation for ewes is an efficient way (Arco et al, 2021;Campos et al, 2022). This is because the birth weight of lambs is related not only to the genetic factors of the parents (rams and ewes) but also to the good nutritional conditions of the ewes in the final third of gestation (Heimbach et al, 2020;Poli et al, 2020).…”

“…Lamb supplementation can also be used as a management alternative to increase the reproductive efficiency of ewes during lactation periods (Arco et al, 2021;Campos et al, 2022). The main objective would be to decrease the sucking of milk by the lambs and, consequently, increase the LH pulses, and increase the concentrations of receptors for LH and FSH in the follicles, generating ovulation a few days after delivery (Buso et al, 2018).…”

Non-Destructive Methods Used to Determine Forage Mass and Nutritional Condition in Tropical Pastures

“…[1][2][3][4]. Additionally, destructive methods are also employed to assist in obtaining the accumulation rate and availability of forage mass in research assessing the effect of different defoliation intensities on animal performance in continuous stocking, rotational stocking, and integrated production systems [5][6][7][8][9], as well as in research on feed supplements (e.g., mineral, energy, protein) with forage for ruminant production [10][11][12][13][14].…”